Marin County Parks and Open Space Department

Old Saint Hilarys DetailThe land immediately surrounding this small church was set aside as a historical landmark in the 1950’s, as was the slope below it, which came to be known as the John Thomas Howell Botanical Garden, in honor of the author of the venerable Marin Flora. But the land above and below these parcels was slated for development and didn’t pass into public hands until the 1990’s.

Today, this 122 acre preserve is the only place to see the extremely rare Tiburon jewelflower. This odd member of the mustard family has such dark maroon petals that they appear to be nearly black, thus earning the scientific name Streptanthus niger. These flowers may usually be seen in mid-May along the Vistazo Fire Road, which traverses the lower portion of the preserve. A small, steep trail connects the lower route to the Heathcliff Fire Road that crosses the upper slope. Views from the top of the hill (where the preserve adjoins the Tiburon Uplands Preserve) are fabulous. One can sit atop this windswept slope and fully appreciate how lucky we are to have saved this slice of unique habitat.


North access: from Hwy 101 in Mill Valley, take the exit for Tiburon Blvd (Hwy 131) east 3.5 miles. Turn left onto Lyford Dr, MCOSD gate is at the end.

South access: from Hwy 101 in Mill Valley, take the exit for Tiburon Blvd (Hwy 131) east 3.5 miles. Turn left onto Lyford Dr, right onto Vistazo West St, and follow to the end (dead end).

Visit,,, or dial 511 to find out about alternative transportation and public transit options from your location.

Open Space Field Guide

There’s a resident pair of Great Horned Owls in the Valley, Red-tailed Hawks nesting just above them, and there is usually a pair of American Kestrels here all year too. As you walk along Vistazo Fire Road you might see buckeye butterflies, even in mid winter.

eNature BirdsBirds
eNature ButterfliesButterflies
eNature ReptilesReptiles & Amphibians
eNature MammalsMammals
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Birds, Wildflowers


24 hours

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